ToolsCourseTp3: am2901_ctl.vbe

ENTITY  am2901_ctl  IS

PORT(
    -- Input/Output from and to the data-path.

    -- Command for selecting operands R and S.
    ops_mx : out BIT_VECTOR(2 downto 0);
    opr_mx : out BIT_VECTOR(1 downto 0);
    
    -- ALU commands and auxiliary terminals.
    alu_k    : out BIT_VECTOR(4 downto 0);
    alu_cout : in BIT;
    alu_over : in BIT;
    
    -- RAM, ACCU shifter commands and auxiliary terminals.
    -- ("acc_sh" is same as "ram_sh")
    ram_sh : out BIT_VECTOR(1 downto 0);
    
    -- Output multiplexer commnand (for X bus).
    out_mx : out BIT;
    
    -- ACCU controls terminals.
    -- ("acc_ck" directly comes from the plots)
    acc_wen : out BIT;
    
    -- Data bus terminals.
    alu_f  : in BIT_VECTOR(3 downto 0);
    alu_np : in BIT_VECTOR(3 downto 0);
    alu_ng : in BIT_VECTOR(3 downto 0);
    
    -- Input/Output from and to the plots.
    
    -- ALU terminals from/to plots.
    -- core_ncout :   out BIT;
    core_np   : out BIT;
    core_ng   : out BIT;
    core_over : out BIT;
    core_zero : out BIT;
    
    -- RAM, ACCU shifter terminals from/to plots.
    -- RAM and ACCU I/O plots controls.
    core_sh_right : out BIT;
    core_sh_left  : out BIT;
    
    -- Data bus terminals from/to the plots.
    i : in BIT_VECTOR(8 downto 0);
    
    noe : in  BIT;
    oe  : out BIT;
    
    -- + 
    a : in BIT_VECTOR(3 downto 0);
    b : in BIT_VECTOR(3 downto 0);
    
    deca  : out BIT_VECTOR(15 downto 0);
    decb  : out BIT_VECTOR(15 downto 0);
    decwb : out BIT_VECTOR(15 downto 0);
    
    -- Power supply connectors.
    vdd : in    BIT;
    vss : in    BIT
    
    );

END am2901_ctl;
 

ARCHITECTURE  behavior_data_flow  OF  am2901_ctl  IS

    -- Internals bus.
    SIGNAL alu_p : BIT_VECTOR(3 downto 0);
    SIGNAL alu_g : BIT_VECTOR(3 downto 0);
    -- Internals signals.
    SIGNAL ram_wri : BIT;
    SIGNAL interm : BIT_VECTOR (15 downto 0);

BEGIN

    -- *************** ACCU and RAM multiplexer control **************
       
    -- Completer
    
    -- ******************** S multiplexer control ********************
    
    -- Completer
    
    -- ******************** R multiplexer control ********************
    
    -- Completer
    
    -- ******************** X multiplexer control ********************
       
    -- Completer 
    
    -- ************************* ALU control *************************
    
    -- ** ALU commands **
    
    -- Completer
    
    -- ** Compute of ALU flags **
    -- * Propagate *
    
    -- Completer    
    
    -- * Generate *
    
    -- Completer
    
    -- * Zero and Overflow *
    
    -- Completer
    
    -- ************************* ACCU control ************************
    
    -- Compute of ACCU write enable.
    
    -- Completer
    
    -- ************************** RAM control ************************
    
    -- ** Compute of RAM write enable **
    
    -- Completer
    
    -- ** RAM and ACCU I/O plots controls **
    
    -- Completer
    
    -- ** RAM shifter I/O **
    
    -- Completer
    
    -- + 
    
    -- Completer

END  behavior_data_flow;